1. Technical Field
The present invention relates to an image display medium and to an image display device equipped with the image display medium. In more detail, the present invention relates to an image display medium that carries out image display repeatedly by moving, by an electric field, charged particles that are enclosed between a surface substrate and a back substrate of the image display medium, and to an image display device that carries out image display repeatedly on the image display medium.
2. Related Art
Image display media using colored particles have conventionally been known as image display media that have a memory property and at which repeated re-writing is possible. Such an image display medium is structured to include, for example, a pair of substrates, and plural kinds of particle groups that have different colors and charge characteristics and that are enclosed between the substrates so as to be able to move between the substrates due to an applied electric field. Further, there are also cases in which gap members, for partitioning the region between the substrates into plural cells, are provided between the substrates for reasons such as preventing the particles from tending toward a partial region between the substrates, and the like.
In such an image display medium, the particles are moved by applying a voltage corresponding to an image to between the pair of substrates, and the image is displayed as the contrast of the particles of the different colors. Note that, even after the application of voltage is stopped, the particles remain adhered to the substrates due to van der Waals force and image force, and the image display is maintained.
In order to improve the color display ability in an image display medium of such a structure, in addition to color display by particles, using a colored back substrate and displaying the color of the back substrate.
Further, using a colored liquid as a liquid enclosed together with particles between substrates, and displaying the color of the colored liquid has been proposed.